The rods and the cones are the two different types of photoreceptors. The unique sense cells known as photoreceptors can absorb light photons and contain photopigments. The photoreceptor tip is encircled by microvilli on the apical surface of the RPE cell. Between Bruch’s membrane and the neurosensory retina, a single layer of RPE cells that are joined to one another along their sides. The RPE cell is a cuboidal cell with a hexagonal shape that is located behind the photoreceptors. Retinal Pigment Epithelial Cells (RPE cells) Ganglion cells create second-order neurons, while bipolar cells are first-order cells. Sensory receptors include photoreceptors. In a three-step journey through the retina, the photoreceptor cells, bipolar cells, and ganglion cells carry the neurological signal. Amacrine cells and horizontal cells, two more significant neurons, play supporting roles. The three types of neurons that make up the majority of the neurosensory retina are photoreceptors, bipolar cells, and ganglion cells. The retina’s thickness ranges from 110 to 140 m in the peripheral region, and increases as it moves towards the posterior pole. On the temporal side, the distance from the optic disc to the ora serrata is 23–24 mm, while on the nasal aspect, it is roughly 18.5 mm. The remaining retina is referred to as the peripheral retina. There are typically four vortex veins (one in each quadrant), but there could be up to ten. In each of the eye’s four quadrants, the choroidal veins empty into a vortex vein. Finding the vortex veins is clinically one of the simplest ways to detect the fundus’ equator. The fundus’s equator is located 14 to 15 mm or so away from the limbus. It is located between the superior and inferior temporal arteries. The retina’s area centralis is a circular region with a diameter of 5–6 mm. 2 The retina has an average thickness of 200 micrometres it is slightly thicker between the macula and the optic nerve head and gradually becomes thinner at the ora serrata and the fovea. Layers of Retina- The human retina has a surface area of around 1,100 square millimetres and measures 32 millimetres from ora to ora along the horizontal meridian. Layers of Retina Anatomy Anterior to Posterior Know All About Human Eye Layers of Retina Diagram Layers of Retina Layers of Retina Physiology The black pigment melanin in the pigment layer reduces light reflection around the globe of the eyeball, which is crucial for good vision. The neural retina is nourished and supported by this layer, which is closest to the choroid.
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